-LRB- CNN -RRB- -- Along with math , science and social studies , gun safety could soon be part of the first-grade curriculum in some Missouri public schools .

A new measure that advocates for such classes for first-graders was signed into law last week . But the idea has prompted worry from some parents and experts about the role and effectiveness of gun safety programs in a classroom setting .

`` I do n't have a gun . My family does n't have a gun . There is no reason for them to be teaching about gun safety when there are children with parents like me , '' Aimee Patton , a Kansas City blogger and mom to a 6-year-old girl , told CNN in a phone interview .

Though her child attends school in Kansas , Patton has been openly critical of the bill in her blog , Pleasantly Eccentric , since the legislation was introduced one day before the Sandy Hook Elementary School shooting last December . Twenty children -- all of them first-graders -- and six adults were killed at the Newtown , Connecticut , school by a lone gunman .

The measure signed Friday by Missouri Gov. Jay Nixon is part of the larger public safety bill HCS/SB 75 . It encourages schools to teach gun safety to first-graders through courses such as the National Rifle Association 's `` Eddie Eagle '' Gunsafe Program .

`` The purpose of the program will be to promote safety and protection of children and emphasize how students should respond if they encounter a firearm , '' says the bill , which was sponsored by state Sen. Dan Brown , a lifetime member of the NRA .

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The legislation prohibits school personnel and instructors from making judgments about guns or from using firearms to teach the program .

Brown told CNN in an interview that Sandy Hook did n't spur any changes in the law , which he said had been percolating for years .

`` It became more relevant after Sandy Hook , '' Brown said , also noting that he did not talk with the NRA about the measure .

Brown believes kids unfamiliar with guns are more likely to play with them and pull the trigger . Kids who grow up with guns , `` they get it . ''

A number of other states have taken steps encouraging schools to promote gun safety .

The NRA noted the Missouri law 's signing on its legislative website , but the group did not respond to efforts seeking additional comment .

But in testimony before the U.S. Senate earlier this year , NRA Executive Vice President Wayne LaPierre said the group has a `` long and proud history of teaching '' safe and responsible gun ownership across the board and to kids , in particular .

`` Our ` Eddie Eagle ' children 's safety program has taught over 25 million young children that if they see a gun , they should do four things : `` Stop . Do n't touch . Leave the area . Tell an adult , '' he said .

Eddie Eagle is a mascot dressed as an eagle who addresses gun safety issues for children in pre-K through third grade .

`` The purpose of the ` Eddie Eagle ' Program is n't to teach whether guns are good or bad , but rather to promote the protection and safety of children , '' the organization 's website says , adding that its purpose is to prevent accidents .

Scott Holste , a Nixon spokesman , told CNN the program is optional for school districts and is not mandated under the new law , which authorizes schools to seek public grants to fund safety programs .

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Conflicting opinions

Still , Amy Jordan Wooden , a Missouri resident and mother of two young children , thinks gun safety should stay out of her kids ' classrooms .

`` I think I 'm a lot more interested in teachers and the legislature being focused on math , science and reading for our first-graders instead of an NRA curriculum . I trust the parents to teach the kids properly about the power of guns . That is where the responsibility lies , not in a school curriculum , '' she said .

Other parents disagree .

`` There are too many kids who grab the guns and kill their cousins . I agree , I think they should know gun safety . It would be helpful , '' Cathy Peters told CNN affiliate KCTV .

Two studies critical of gun safety programs

Pediatricians and gun safety experts say , however , that the efforts behind the measure may be misguided .

For instance , a 2004 study on firearm-related injuries in children , published by the American Academy of Pediatrics , found that gun safety programs for children were ineffective , `` do not prevent risk behaviors and may even increase gun handling among children . ''

Another 2004 study of the `` Eddie Eagle '' program , published by North Dakota State University 's Department of Psychology , found that children were able to verbally repeat the program 's message , but when they encountered a gun in a role-playing scenario , they were unable to put the skills to use .

The North Dakota study said one shortcoming of programs like `` Eddie Eagle '' was the absence of active learning approaches .

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`` Information-based programs are less successful because they do not actively allow the children the opportunity to practice the skills being taught , '' the study said .

Former police investigator and gun safety expert Steve Albrecht said `` kids do n't have the emotional maturity at that age . ''

Albrecht is a security consultant for schools and workplaces and is also a parent . He said schools have to play a bigger role in the gun safety discussion but `` in concert with the parents . ''

`` Part of the issue has to be educating the parents to keep the guns secure first . Because it does n't matter if the kids have been to a gun safety program or not , '' said Albrecht .

Patton agrees . She said the responsibility behind gun safety lies with parents and not with teachers .

But LaPierre told the Senate in January that `` teaching safe and responsible gun ownership works '' and stressed that firearms accidents are at their lowest levels in more than 100 years because of safety programs like `` Eddie Eagle . ''

Brown said first-graders should n't be doing experiential learning with guns and felt the `` Eddie Eagle '' video would be enough .

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CNN 's Bryan Koenig contributed to this report .

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Missouri governor signed NRA-backed law last week

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Some experts say such programs do n't work

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Bill was sponsored by a state senator who is an NRA member

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Critics say gun safety is the responsibility of gun owners